June 13 (Reuters) - Exxon Mobil Corp and Saudi Basic Industries Corp said on Thursday they would start construction of a $9 billion petrochemical plant in Texas in the third quarter that would have the world's largest ethane processing capacity.

The 50/50 joint venture, called Gulf Coast Growth Ventures, will have the ability to produce 1.8 million metric tons a year, and will house a monoethylene glycol unit and two polyethylene units, the companies said.

The project, located north of Corpus Christi, is expected to be operational by 2022.

Building the world's largest steam cracker on the doorstep of rapidly growing Permian production gives this project significant scale and feedstock advantages, Exxon Mobil Chief Executive Officer Darren Woods said.

Oil producers and refiners see petrochemicals as a growing market for their crude as demand for motor fuels is expected to plateau with the advent of electric cars and more efficient homes and offices.

The project is expected to create more than 600 permanent jobs, the companies said, adding that the facility will produce materials used in the manufacturing of various consumer products such as automotive coolants, packaging and construction materials.

Construction of the project will be led primarily by Wood Group, McDermott & Turner Industries Group, Chiyoda & Kiewit, Mitsubishi Heavy Industries and Zachry Group, according to the statement. (Reporting by Arundhati Sarkar in Bengaluru; Editing by Anil D'Silva)